Garnet

Overview

Garnet is a group of silicate minerals with the same crystal structure but different chemistry. Most people picture a deep red stone, but garnets also come in fiery orange, vivid green and soft pink. Garnets are singly refractive, usually untreated, and offer excellent value.

The main gem garnets

Key properties

Where garnets come from

Mozambique and Tanzania produce fine pyrope–almandine and rhodolite. Tsavorite comes from Kenya and Tanzania, mandarin spessartine from Namibia and Nigeria, and demantoid from Russia's Ural mountains, Namibia and Madagascar. Sri Lanka and India are long-standing sources.

Treatments

Garnet is one of the few gems that is almost never treated, which makes it a good choice for buyers who prefer untouched stones.

Buying tips

• Brightness matters most for red garnet. Many are so dark they look black; choose stones that stay lively in ordinary indoor light.
• Rarer species cost more. Tsavorite and demantoid are priced far above red garnet; ask for a report on larger stones.
• Demantoid's "horsetail" inclusions (fine curved fibres) are prized, especially in Russian stones.

Care and cleaning

Clean with warm soapy water and a soft brush. Ultrasonic cleaners are generally safe for stones without fractures, but avoid steam and sudden temperature changes. Softer garnets such as demantoid are better suited to earrings and pendants than everyday rings.